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1.
Abstract The present study was designed to establish the susceptibility of macrophage-mediated effector functions to tetanus toxin (TT). Using the murine macrophage cell line, GG2EE, generated in vitro by v- raf /v- myc oncogenes, we have previously provided evidence that TT selectively inhibits interferon gamma (IFN-γ), but not basal, lysozyme activity. Here we show that while neither phagocytic nor candidacidal activities are affected by TT treatment, antitumoral activity is significantly impaired after exposure to TT. This phenomenon, which is dose-dependent, is fully ascribed to the holotoxin, as heat inactivated TT, C or A-B fragments result ineffective. Furthermore, C but not A-B fragment competes with TT in abrogating its inhibitory effects. Overall, these data indicate that TT is not a broad-spectrum, down-regulating signal on macrophage-mediated functions, thus implying that its toxic action is exerted on specific molecular targets.  相似文献   
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Vegetation History and Archaeobotany - Studies of the origins of agriculture in the Near East have revealed that the eight plant species known as “Founder Crops”, i.e. emmer, einkorn,...  相似文献   
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4.

Introduction

In this study, 27 genetic polymorphisms that were previously reported to be associated with clinical outcomes in colorectal cancer patients were investigated in relation to overall survival (OS) and disease free survival (DFS) in colorectal cancer patients from Newfoundland.

Methods

The discovery and validation cohorts comprised of 532 and 252 patients, respectively. Genotypes of 27 polymorphisms were first obtained in the discovery cohort and survival analyses were performed assuming the co-dominant genetic model. Polymorphisms associated with disease outcomes in the discovery cohort were then investigated in the validation cohort.

Results

When adjusted for sex, age, tumor stage and microsatellite instability (MSI) status, four polymorphisms were independent predictors of OS in the discovery cohort MTHFR Glu429Ala (HR: 1.72, 95%CI: 1.04–2.84, p = 0.036), ERCC5 His46His (HR: 1.78, 95%CI: 1.15–2.76, p = 0.01), SERPINE1 −675indelG (HR: 0.52, 95%CI: 0.32–0.84, p = 0.008), and the homozygous deletion of GSTM1 gene (HR: 1.4, 95%CI: 1.03–1.92, p = 0.033). In the validation cohort, the MTHFR Glu429Ala polymorphism was associated with shorter OS (HR: 1.71, 95%CI: 1.18–2.49, p = 0.005), although with a different genotype than the discovery cohort (CC genotype in the discovery cohort and AC genotype in the validation cohort). When stratified based on treatment with 5-Fluorouracil (5-FU)-based regimens, this polymorphism was associated with reduced OS only in patients not treated with 5-FU. In the DFS analysis, when adjusted for other variables, the TT genotype of the ERCC5 His46His polymorphism was associated with shorter DFS in both cohorts (discovery cohort: HR: 1.54, 95%CI: 1.04–2.29, p = 0.032 and replication cohort: HR: 1.81, 95%CI: 1.11–2.94, p = 0.018).

Conclusions

In this study, associations of the MTHFR Glu429Ala polymorphism with OS and the ERCC5 His46His polymorphism with DFS were identified in two colorectal cancer patient cohorts. Our results also suggest that the MTHFR Glu429Ala polymorphism may be an adverse prognostic marker in patients not treated with 5-FU.  相似文献   
5.
It is accepted that angiogenesis plays an important role in the development of the corpus luteum (CL) and is probably necessary for normal lutein cell function. A number of drugs currently being tested in clinical trials as possible angiogenesis inhibitors were not originally developed with the intention of suppressing tumor angiogenesis. Interferon alpha (IFN-alpha) is one of the notable examples of such 'accidental angiogenesis inhibitors' and daily administration of IFN-alpha is known to suppress tumor growth, tumor vascularization, and down-regulation of various growth factors. We investigated the effects of IFN-alpha treatment on the expression of vascular endothelial growth factor (VEGF), and its receptors KDR and Flt-1, and CD34 in CL during the first week of pseudopregnancy and pregnancy in hormonally induced rat ovaries by immunohistochemistry and Western blot techniques. Basal body temperatures of the drug-treated rats, as an indicator of treatment effect, were determined daily and were increased significantly when compared to controls (38.03 +/- 0.18 vs. 36.6 +/- 0.1 degrees C), respectively. The effect of IFN-alpha treatment was minimal when the entire week was evaluated, however, the expression of VEGF decreased at 3rd, 5th, and 7th days of both pregnancy and pseudopregnancy, when compared to the 1st day, whereas there was not a such alteration in the untreated rats regarding these days. The daily subcutaneous administrations of 672.500 U IFN-alpha2b had minimal effects on the expressions of VEGF, and its two receptors KDR and Flt-1 in either pregnant or pseudopregnant corpora lutea utilizing HSCORE.  相似文献   
6.
Recently, mutations in USH1C were shown to be associated with Usher syndrome type IC, and a mutation (216G-->A) in exon 3 was identified in an Acadian family. In addition, a 45-bp variable number of tandem repeat (VNTR) polymorphism was found in intron 5 of USH1C. Polymerase chain reaction amplification of the VNTR region and restriction enzyme analysis of exon 3 of USH1C showed that, of 44 Acadian patients, 43 were homozygous for both the 216G-->A mutation and nine repeats of the VNTR, with a "t" nucleotide replacing a "g" nucleotide at the 8th position of both the eighth and ninth copies of the repeat, viz., 9VNTR(t,t). The remaining Acadian patient was reported to be a compound heterozygote for 216G-->A/9VNTR(t,t) and 238-239insC, a USH1C mutation that has been found in other populations. These data demonstrate that the 9VNTR(t,t) allele is in complete linkage disequilibrium with the 216G-->A mutation in the Acadian population. Among 82 Acadian controls, one was heterozygous for 216G-->A/9VNTR(t,t). The 238-239insC mutation was not found in Acadian controls. Analysis of 340 non-Acadian normal samples showed the presence of a 9-repeat VNTR allele in one Hispanic sample. This individual had neither the 216G-->A mutation nor the Acadian VNTR(t,t) structure. These results suggest that the 216G-->A mutation and the 9VNTR(t,t) allele are restricted to the Acadians and are in complete linkage disequilibrium.  相似文献   
7.
Deletions of the spinal muscular atrophy (SMA)-determining gene, SMN1, NAIP, and a third multicopy gene, BTF2p44tel were investigated in 60 unrelated Turkish SMA patients. SMN1 was deleted for at least exons 7 and 8 in 85% of the Turkish SMA patients. The NAIP gene was deleted in 75 and 33% of type I and type II SMA patients, respectively. Analysis of the 5'end of the BTF2p44tel gene indicated the extension of deletion in 13.3% of the cases, mainly in type I patients. Deletions of the NAIP and BTF2p44tel genes were detected in 1.3 and 3.9% of carrriers, respectively, in Turkish SMA families. Two patients were detected to harbor the hybrid SMN gene, one type II with deletion of the NAIP gene, and one type III without deletion of the NAIP gene.  相似文献   
8.
Long-lived proteins (LLPs) have recently emerged as vital components of intracellular structures whose function is coupled to long-term stability. Mitochondria are multifaceted organelles, and their function hinges on efficient proteome renewal and replacement. Here, using metabolic stable isotope labeling of mice combined with mass spectrometry (MS)–based proteomic analysis, we demonstrate remarkable longevity for a subset of the mitochondrial proteome. We discovered that mitochondrial LLPs (mt-LLPs) can persist for months in tissues harboring long-lived cells, such as brain and heart. Our analysis revealed enrichment of mt-LLPs within the inner mitochondrial membrane, specifically in the cristae subcompartment, and demonstrates that the mitochondrial proteome is not turned over in bulk. Pioneering cross-linking experiments revealed that mt-LLPs are spatially restricted and copreserved within protein OXPHOS complexes, with limited subunit exchange throughout their lifetimes. This study provides an explanation for the exceptional mitochondrial protein lifetimes and supports the concept that LLPs provide key structural stability to multiple large and dynamic intracellular structures.  相似文献   
9.
Coenzyme Q10 is an important component of mitochondrial electron transport chain and antioxidant. Hyperthyroidism manifests hyperdynamic circulation with increased cardiac output, increased heart rate and decreased peripheral resistance. The heart is also under the oxidative stress in the hyperthyroidism. The aim of this study was to examine both how the coenzyme Q10 can affect heart ultrastructure in the hyperthyroidism and how the relationship between nitric oxide synthase (NOS) and heart damage and coenzyme Q10. Swiss Black C57 mice received 5 mg/kg L-thyroxine. Coenzyme Q10 (1.5 mg/kg) and L-thyroxine together was given to second group mice. Coenzyme Q10 and serum physiologic were applied to another two groups, respectively. All treatments were performed daily for 15 days by gavage. Free triiodothyronine and thyroxine were increased in two groups given L-thyroxine; thyroid-stimulating hormone level did not change. Hyperthyroid heart showed an increased endothelial NOS (eNOS) and inducible NOS (iNOS) immunoreactivity in the tissue. Coenzyme Q10 administration decreased these NOS immunoreactivities in the hyperthyroid animals. Cardiomyocytes of the hyperthyroid animals was characterized by abnormal shape and invaginated nuclei, and degenerative giant mitochondria. Desmosome plaques reduced in density. In hyperthyroid mice given coenzyme Q10, the structural disorganization and mitochondrial damage regressed. However, hearts of healthy mice given coenzyme Q10 displayed normal ultrastructure, except for increased mitochondria and some of them were partially damaged. Coenzyme Q10 increased the glycogen in the cardiomyocytes. In conclusion, coenzyme Q10 administration can prevent the ultrastructural disorganization and decrease the iNOS and eNOS increment in the hyperthyroid heart.  相似文献   
10.
We document anatomic, molecular and developmental relationships between endothelial and myogenic cells within human skeletal muscle. Cells coexpressing myogenic and endothelial cell markers (CD56, CD34, CD144) were identified by immunohistochemistry and flow cytometry. These myoendothelial cells regenerate myofibers in the injured skeletal muscle of severe combined immunodeficiency mice more effectively than CD56+ myogenic progenitors. They proliferate long term, retain a normal karyotype, are not tumorigenic and survive better under oxidative stress than CD56+ myogenic cells. Clonally derived myoendothelial cells differentiate into myogenic, osteogenic and chondrogenic cells in culture. Myoendothelial cells are amenable to biotechnological handling, including purification by flow cytometry and long-term expansion in vitro, and may have potential for the treatment of human muscle disease.  相似文献   
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